Symbiosis
by xChiyuki
Summary: There are some parasites that question their humanity. Upon meeting Kayoko Kenzaki, a girl who smiles in the face of death, Hideo Shimada finds himself facing a conflict between the creature that he is and the man that she believes him to be. But as Kayoko confronts her own fears, Hideo is forced to confront her mortality. Hideo Shimada/OC.
1. fear

Parasyte -the maxim-  
Symbiosis  
Chapter 1: Fear

One thing that Kayoko Kenzaki never expected was to openly welcome death as it approached her.

* * *

The school bell rang loudly, making her jump in her seat as it shook her from her thoughts. She took a deep breath, sighing as she pressed her hand against her racing heart in an attempt to calm herself down.

"Kayoko!" called Akiho, the most rambunctious of her friends. She waved at Kayoko from the doorway, where a group of three girls stood, waiting for her. "C'mon, let's go! You said we could hang out today!"

She smiled sadly. She hadn't been able to spend time with her friends since her parents died, almost two months ago now. Standing, she picked up her bag and approached Akiho, Satomi, and Yuko, who stood at the front door of the classroom, waiting for her.

"I can't stay out long," she said quietly, trying to seem cheerful. "Hiroshi's still pretty worried about me being out so late. He doesn't want what happened to mom and dad to happen to me."

Akiho and Yuko both cooed at her boyfriend's fierce protectiveness, but Satomi looked at Kayoko with what seemed like suspicion. Ever since Kayoko moved in with Hiroshi, her older boyfriend of almost a year now, after the deaths of her parents, she hadn't been making much time for the rest of her friends. Her excuse was always that Hiroshi was worried about her, but Satomi thought otherwise.

She was too jumpy nowadays. She was always looking down, never making eye contact unless she was spoken to first. She even got scared when Shinichi, her childhood friend, put his hand on her shoulder. Something was very wrong with Kayoko, and Satomi couldn't figure out for the life of her what it was.

But for now, it was no matter.

Kayoko was here, with her friends. She was away from Hiroshi, even if it was just for a little while. Whatever was wrong didn't matter right now.

* * *

The dark apartment was somewhat terrifying, especially since Kayoko knew what awaited her inside. It was six, much later than the time she normally came back. Even if she had texted him beforehand, he would still be angry.

"I'm… I'm home," she called nervously, peering into the apartment hallway.

A voice came from the living room, where the only light was on. "About time. You're late, Kayoko." She flinched, hearing the apathy in Hiroshi's voice. She slowly crept into the living room, seeing the gruesome news about the mincemeat murders on the television. Hiroshi turned to look at her, a blank expression on his face, although his angered eyes contradicted his façade of calmness. "Tell me why you're so late."

She could feel dread creep down her spine as she shook. She wished she could be braver, but there was no way that she could even look at him without feeling some sort of fear. "I… I was late because I was with my friends. We went to Shibuya," she replied, not bothering to argue.

"Are these the friends I met at your parents' funeral?" Kayoko nodded, fear lacing her heart. "I thought I told you that you don't need them."

Swallowing nervously, she summoned enough courage to look him in the eye. "But I missed them. I haven't spent any time with them since the funeral…" His glare made her trail off.

"What did I say about talking back?!"

Kayoko felt the stinging pain in her cheek as she whimpered softly, her hair whipping into her eyes. Tears pricked her eyes as she fell to the floor, her body steeling itself for the pain that she knew was coming. She bit back her sobs as she closed her eyes and prayed for it to be over.

* * *

The parasite didn't know where it was.

It knew one thing, and one thing only – it had to find a living host. It had to find something with a brain that it could take over. It had to find something that it could survive in.

A soft sobbing sound reached its receptors. It perked, somehow knowing that the sound was being made by a living being. It could follow that sound. From its pod, the parasite crawled, slipping through the night air until it found something, slipping into the human's warm flesh, burrowing through its skull.

It knew that it would live.

Its consciousness began to blossom upon this realization, spurring itself into the fullest of sentient beings. It stood, looking down at itself, at its new body. Its hands were callused and rough, its knuckles missing skin as they bled through the poorly done bandages. It was a male in its late adolescent stages. That was the first bit of information that the parasite absorbed.

Information from the being's mind came flooding in. All of its knowledge, all of its memories… everything but the knowledge of emotion. The parasite registered that there were emotions, but could not register how they felt. But it – he – became aware of one very important thing.

By human standards, the male he was inhabiting was a disgusting being.

Human males treasured their significant others and treated them with respect. There was the idea that all life was precious, that men should protect the women. But this male, Hiroshi Yamanaka, did not. He did not respect his significant other. Instead, he treated her like she was worth nothing.

The parasite felt himself frowning. He moved slowly from the room he was in, nearly tripping as he adjusted to walking. He looked through the living space. He heard the sobbing he had followed, and decided to follow it once more. His face, the face he had inherited from his host, began to split. His blades were sharp enough to kill, despite the fact that he had only just matured. He had to sustain himself somehow. He was a human, and he knew that humans were his food source.

He walked into a room that smelled like oil and smoke. It smelled like human food. On the floor, her body curled into a ball, was the girl he had seen in his host's memories. She was shaking and crying. Her skin was red with what looked like blood, which dripped down and spread over the floor.

Upon hearing his footsteps, she slowly looked up. Her eyes met his. His blades pushed themselves forwards, poised threateningly near her body. One stopped near her neck, prepared to slice her thin skin open.

She smiled as she looked up. The parasite was taken aback.

According to his host's memories, humans feared death. She should have screamed.

But instead, she sat up so she could face him, that smile still on her face. His blade followed her almost curiously. She looked content, peaceful, despite the tears running down her face. "Go ahead," she muttered. "You're going to kill me, right? That's okay. Just, please, make it painless. I'm tired of hurting…"

He remembered that his host had beat her that night. His host had beaten this girl until she bled.

"Did you kill Hiroshi?"

She had cried and cried, begging for him to stop.

"… I'm glad, then…"

The parasite wondered just what this girl was. She was human, but she had made peace with the possibility of death. She had accepted that she was weak.

Making a decision, he retracted his blades. His head reformed itself, but his face was different. He did not want to wear the face of the man who had hurt her. It would only scare her more. Instead, he chose a softer face, mimicking the one he had seen in his host's memories, but he could not place where.

Her eyes widened as he knelt before her. "Where does… it hurt…" he slowly managed, his words clunky as he spoke. His speaking was broken, but she understood. She slowly, shakily, pointed to her side, where there was blood leaking through her shirt, spreading through the fabric.

"Hiroshi… did this," she whispered. "He stabbed me with a screwdriver… He managed to avoid anything vital, though… He just wanted me to suffer… Not die."

The parasite stood, walking to the living room. He understood that there was information to be found on something called a "computer." He recognized the small, thin, black rectangle that sat on a small block of wood. Opening it, he searched "stop bleeding."

There was more information than the parasite knew what to do with. His eyes scanned it, absorbing all of the words. He slowly stood after digesting as much of the words as he could and returned to the food room.

He found a white cloth in one of the drawers. It was soft in his hands. He knelt near the girl again and pushed down on her side with the cloth. She winced, but didn't move. He moved her hand to the cloth, pushing her hand down on her wound. She seemed to understand as she held her hand there, the white cloth dyed red. He stood walking to the counter, where he pulled a small box from another drawer.

Inside, there was white, web-like cloth. It was called "gauze" according to his information. There was also thin, brown cloth with a sticky side. He picked up both and returned to the girl. He gently pulled the bloody cloth away from her, instead pressing the gauze down onto her wound, then holding it down with a few strips of the brown cloth. He was well aware of her eyes on him.

"Why are you helping me?" she asked softly.

He looked up at her. "Because I want to know… why you do not fear death." His answer was a bit more put together than his previous sentences. Perhaps it was because he was beginning to understand the information he had inherited.

The girl smiled a little. "You're nicer than Hiroshi. I'm sure you could have killed me if you wanted, but you didn't. Thank you… for saving my life." She looked up at him, her warm eyes filled with the life that his were not.

Somehow, he noted it was good that he kept that light from dying.

* * *

Kayoko still didn't know what had taken over Hiroshi's body. She just knew that it was some sort of alien bug that infected and devoured his brain. It learned fast. Every day, it became more and more intelligent. It wasn't a violent being, just a curious one. After that night, it hadn't brought out its blades even once.

Within two days, it had mastered human speech. Within a week, it'd learned how to hide itself as a human being. Within a month, it had become as human as she was.

"Kayoko," it called one day as it watched a news report on the television. "These mincemeat murders on TV. Do you think that they're caused by others of my kind?" It turned to look at her, its blank eyes trained on her figure.

She'd been exposed to what the parasite could do early on. After its blades nearly ended her life, she was sure that there were others. She was sure that those things were what caused the murders that took up all of the daily news, sure that those things were what had killed her parents.

She hesitated to tell him. There was no telling what it would do if it knew that there were more. But she nodded. "Yes. I'm sure there are others," she replied, turning back to the stove.

It hummed. "You knew?" She nodded again. "Then…" it appeared right in front of her face, distracting her as she cooked, "… why haven't you called the cops on me? Aren't you scared you'll end up next?" it asked, staring at her.

She stared into its blank eyes, unflinchingly. "If I'm still alive, then I'm not afraid. Honestly, if you haven't killed me, I doubt you've killed anyone else. I'm more afraid for others than I am for myself," she admitted, looking back down to the raw meat she was cutting through, her knife in her right hand.

The parasite had a huge appetite. It claimed that because it was a superior being – at least physically – that it needed extra food. She accepted that as an easy solution, and always made sure to make him extra food whenever she could. Yet it always preferred near-raw meat, even after it tried many human foods.

"Does that mean you don't care if you die?"

It always had a lot of questions. Some were easy, like "what is that" in reference to the television. Others were more difficult. One time, it had asked her why she got so much enjoyment out of listening to music as she cooked. Another time, it asked her why she woke up screaming several nights.

But to Kayoko, this question was easy.

"No. I don't." She sighed as she marinated the steak. "The way I see it, you saved my life the night that you killed Hiroshi. I'm in your debt. If you ever felt the need to kill me, you probably could. And I accepted that when I decided to stay here. It doesn't mean I'm scared, it's just that I've come to terms with it."

The parasite's gaze fixed itself on her, even as she turned away, starting up the table grill.

"You're a strange one," he finally said, returning its gaze to the television. "Most humans fear dying, don't they? Isn't that why they go to such lengths to extend their lives?"

She just laughed dryly. "Yeah, well, if you wanted someone who would beg for their lives, you found the wrong human."

The look of defeat and tiredness didn't look quite right on Kayoko's face as he studied her. The parasite decided that she needed to be happy or alive, needed to have the look he'd first seen that night. It wasn't because he preferred it or anything like that.

It was simply what he deemed to be right.

* * *

 _Hello, my name is Chiyuki, and welcome to "Symbiosis." I'm sure a canon/OC fanfiction for this series is a strange thing to see, but please give it a try. I truly love this piece._

 _There will be points in time that I feel I've taken Hideo and some of the parasites (Migi in particular) out of character, but I tried to balance it out by showing their thought process behind those actions. I know that most of the time, it may not work for everyone, but I hope you can forgive me. I've also altered the canon of parasites a bit, changing some of their lore to better fit what I'm attempting to do with this story. The ending will be slightly AU, as well. Please forgive me if you dislike anything I've done with the canon._

 _This piece will take place before and during episodes 8-10, not focusing on Shinichi, but the birth of Hideo Shimada and his life blending in as a human. I added Kayoko to represent the best of humanity, simply in order to balance out Shimada and his personality in the episodes._

 _Please enjoy, and leave a review to tell me what you think. Thank you._

 _-Chiyuki_


	2. name

Parasyte -the maxim-  
Symbiosis  
Chapter 2: Name

"Hideo. Hideo Shimada."

* * *

It'd been another month before the parasite found one of his own. This one was a woman. She was pregnant, but she was definitely like him. She walked right up to him in broad daylight and introduced herself as Reiko Tamura.

Kayoko had been with him, and had stared between the two with both confusion and realization. He glanced to her and handed her the bags filled with the groceries they'd bought that day. "I'll be home soon," he assured her, pushing her away as gently as he could.

She'd nodded and scurried away. After two months of living with him, she had grown used to his presence. After the first month, she'd stopped going to school, citing health reasons to leave the school. Whenever she had to take an exam to prove something about still learning through her time off, he helped her, as his capacity to absorb information was greater than hers.

She stayed home to take care of him, to ensure that he could blend in with humans. Although his capacity for information was greater than hers, there were things that he did not understand. Whenever those came up, he asked her, and she would always provide information to the best of her ability.

They discovered that other parasites, like him, were dangerous, flesh-eating monsters. It was why there was so much attention on the mincemeat murders. Most of the parasites were bloodthirsty, but this parasite didn't quite understand why they were.

Until Reiko Tamura showed him.

Devouring human flesh did wonders for regenerating energy. Had he known before, perhaps Kayoko would not have survived as long as she did. Had he known before, perhaps he would have killed her rather than have saved her. He immediately forgot about that thought, as it was only right that she stayed alive.

"Why haven't you killed the girl yet?" Reiko asked during one of their bimonthly outings.

"Because it isn't right to kill her," he replied.

She smirked. "Is it because you have feelings for her? Any kind?" Her tone was interested, but sarcastic.

The parasite looked up at her, his mouth bloody from the flesh. "No. It has nothing to do with preference or emotions. It's because it would be wrong if she wasn't alive." He said this like it was the most obvious thing in the world which, to him, it may have been.

Reiko nodded. "I see." There was a lull in conversation, something which never felt so uncomfortable to the parasite. "It's been two months, and I don't know your name."

For a moment, he thought. "I don't have one."

"You should. Don't you know your host's name?"

He scoffed. "Of course. But using his name is wrong," he replied easily.

Narrowing her eyes, she watched the other parasite with both curiosity and resentment. "For what reason is using his name wrong?" she demanded dryly, crossing her arms over her bulging stomach.

He glanced at her again, finding no trace of joking on her face. Not like how Kayoko sometimes made jokes with him. "He's a bad person. Using his name is wrong because it makes Kayoko tired. It's not right when she's tired."

Reiko never questioned him again.

* * *

"Kayoko." She looked up at him as they lay on their separate futons. "Should I have a name?"

A gasp came from the dark-haired girl as she shot up in bed. "I can't believe I forgot. It's been four months already, and you still don't have a name?" She sighed. "Why don't you just use… use _his_ name?" she asked, stumbling before saying his host's name.

He shook his head, turning on his side to face her. "No. You can't even use his name. You're scared." She bit her lip. "I want one that you can say. Can you give me one?"

She hesitated, but nodded. "I'll come up with one for you," she vowed.

* * *

Reiko wanted him to transfer into high school.

The high school that Kayoko used to go to.

"I'm not leaving her alone."

"Then take her with you."

He couldn't argue with Reiko's logic. She somehow managed to make the most unpleasant-sounding ideas make some sort of sense. Even if it didn't seem right to him, she managed to change it to make it sound at least a little right.

Turning towards their victim, he sighed, taking another bite of the human flesh. Although he knew that he needed it, somehow, it didn't feel right in his gut. "I don't get it. All this to look after some boy? He sounds like he's more trouble than he's worth," he muttered.

Reiko hummed a little. "In a way, he is," she replied slowly. "But he is special. He is like us, but also like your human. He and the one called Migi are in perfect symbiosis. It is important for us to find out how. For our species to survive."

"I'm alive. I'm surviving. Why is he important?"

"Because you want to keep surviving, don't you?"

He stood, letting his face reform into the face he'd decided to keep after the first night he met Kayoko. "His name is Shinichi Izumi, huh… I guess I'll do it. But only if Kayoko comes with me," he decided, much to Reiko's approval.

* * *

Convincing her was easy.

It was clear from the way she'd practically jumped at the chance to go back to high school that she missed it. She wanted to see people her age again. She must have had friends. According to Kayoko, she'd left in the middle of the current school year. It was nearly September, so she could come back and pick up where she'd left off when she decided to study at home without too much hassle.

"But you're going to need a name…" she murmured. "I'll think of one when I write your transfer papers. Oh, and I have to make up something about your parents. Since you're going to be seventeen, after all… Well, I'd better start soon!"

She seemed happy. It was good. Her entire being seemed lighter as she practically skipped back to their shared bedroom to work. He watched her, something tugging his lips upwards.

He sat down on the couch, picking up his plate. Despite the fact that he'd been out with Reiko and that he'd already eaten in order to keep his strength up, he still wanted to finish Kayoko's food. She'd made it especially for him, after she claimed that he had enjoyed her marinated steak. She made it every week after he agreed with her, although he couldn't tell if he enjoyed it or not.

She once asked if he got sick of it at any point in time. He replied negatively. Half of it was truthful, since he didn't know whether he was "sick of it" or not. The other half was just so she wouldn't look disappointed. It was only right when she was happy.

If going to high school would make her happy, he would do it.

It was only right.

* * *

"Hideo Shimada," she proudly announced, holding up the transfer paper with his new name at the very top of it. "Well?"

He took the papers from her hands. "Hideo like 'splendid man,' and Shimada like 'island rice paddy,' right?" he asked, trying to remember the characters and meanings that he'd learned from borrowing her Japanese textbook.

Kayoko nodded. "Yep! I think it fits you. I took _his_ name and used the sounds as a base. I'm not very good at names, but it works!" She looked so pleased with herself that he couldn't tell her otherwise.

Not that he would. He had no opinion.

"So, everything is set up for us to go to school in a week or two?" he asked, glancing at the uniform she'd hung over his bed. It looked stuffy, but there was a matching one hanging over hers, except his had grey pants and hers had a skirt that was much too short for him to approve of.

She nodded again, beaming. "Yep! We're in class 3 together. I made sure to get us in the same class. It took a little begging, but I'm glad that we're together." She smiled at him.

He mirrored her smile, or tried to. She gaped at him.

"What? Did I do it wrong?"

She shook her head. "No. You look good. I like your smile."

Somehow, he knew that she was completely sincere.

* * *

Kayoko got sick the first week of school.

She came down with a common cold. Her immune system was always a little weaker than most people's, so she got sick a lot as it was. She knew that it was going to be a risk letting Hideo go to school without her, but she knew that he wouldn't hurt anyone in broad daylight.

She knew that he was killing for food now. With that woman, Reiko Tamura. Ever since he met her, his appetite around Kayoko had been lessening. However much he tried to hide it, she saw the blood on his clothes sometimes, even though he tried to wash it before she saw. She somehow knew that he'd become one of the more dangerous ones of his kind, even if he had kept her alive for some reason.

He could've killed her so many times, and no one would ever suspect a thing.

"One of us has to get our schoolwork," she told him as she pushed him weakly out the door, struggling since he'd planted his feet stubbornly and refused to move. He'd stubbornly stayed with her during the first day of school, trying to discern whether or not she was at any risk of getting even sicker. "I think it should be the one who's healthy. Besides, what if you caught what I have?"

"I don't get sick."

He didn't get it. "All the more reason for you to go! Hide, please, I need to rest, and you need to go to school! It's bad to miss if you're not sick!" she protested, looking up at him desperately.

Sighing, Hideo nodded, relenting at the look on her face. "I'll make sure to get your work as well. I'll get what we missed yesterday, too. Okay?"

She nodded with a smile. "Good. I'll make sure there's food on the table for you when you get home," she replied.

He patted her gently on the head. "Don't worry about trivial things like that. Rest now. Get better, so you don't have to send me to school alone." His words were blunt, but not unkind as he turned, walking towards the school.

As she waved him goodbye, she wondered when she started thinking of Hideo as a "he" and not an "it."

* * *

Shinichi Izumi was an interesting person.

He reacted to Hideo the way that he'd assumed Kayoko would. Izumi reacted with hostility, threatening violence, even though Hideo claimed he wasn't violent. Even though the creature in his arm was being more open about giving Hideo a chance, Izumi was stubbornly refusing to give up.

"If I was violent, my body count would be in the double digits. Plus, I wouldn't be living alongside a human," he reasoned, trying to assure Izumi that he was of no threat.

It backfired horribly. Izumi's eyes widened comically, then narrowed until they were mere slits. They felt like they were trying to kill Hideo with just a gaze. "You're living with a human? And you haven't killed them yet? Bullshit."

"Shinichi. He's telling the truth." Migi, the more reasonable of the two, validated Hideo's claims.

Hideo nodded. "Believe me. I wouldn't kill her. It isn't right," he added.

"What the hell does that mean?"

"Exactly what it sounds like. It's not right if she's dead." He paused, seeing Izumi's confusion mix with his hatred. "She knows about me. And she's accepted me as I am. She even gave me my name."

The human boy growled. "I still can't believe you haven't killed her," he mumbled.

Hideo blinked. "I told you. It's not right."

Before Izumi could say anything more, Migi interjected himself into the conversation once more. "You said a human gave you your name. Remind me what it is again," he asked politely. It was nice to talk with someone who was reasonable.

"Hideo. Hideo Shimada."

Migi paused for a moment, clearly going over all of the information in his head. "Hideo Shimada… Interesting choice in name. Especially from a human."

"She said it fit me."

Hideo stood his ground firmly, even asking for Izumi to show him to class 3. If Kayoko were there, he wouldn't need to ask Izumi, but he didn't talk to anyone else, as he'd arrived late and had to fill out some papers, then explain why he missed the first day of classes. Plus, socializing was never part of his mission, or a strong point of his. He'd only ever interacted with Kayoko, and sometimes the people they briefly spoke to when they went out to shop or just get some air.

As Izumi showed him to class 3, he asked, "Why didn't I notice you until today?" Hideo looked towards him, then hummed.

"I was at home yesterday. Kayoko is sick. It's why I was late this morning."

When he said her name, Izumi reacted violently. He grabbed Hideo by the collar and glared at him. "You… you're living with Kayoko? Kayoko Kenzaki?" Hideo nodded, not seeing what was so wrong with that. "You bastard. If you hurt her… I'll kill you," he growled.

Hideo grabbed Izumi's hands and pried them off his shirt. "You're being dramatic. I told you already. It's not right for her to die," he drawled, meeting Izumi's angry gaze with his own calm one.

He could feel Izumi's murderous gaze on his back, but he couldn't pay any attention to it. He knew that, logically, it didn't make sense for Kayoko to die. It wasn't right for her not to have a spark of life in her eyes. He couldn't kill her, because, to him, it would be wrong.

Glancing back, he saw Izumi muttering something to Migi, his right hand.

Whatever it was, it didn't concern him.

* * *

"Migi. What did he mean when he said that… it's not right for Kayoko to die? Does he… feel something for her?"

The eye in his hand blinked at him, as if it was in thought for a moment. "Shimada is one of my kind. He runs on pure logic, not emotion. It's impossible for him to feel anything for her. His logic somehow convinced him that the girl is better off alive." Migi paused for a second. "But when you threatened him, I could feel that he was not angry that you threatened him, but that you insinuated that he would kill her."

Shinichi looked up, his eyes following Shimada's back as he entered class 3. He looked like every other parasite he'd ever seen, especially the eyes. His eyes were as dead as Ryoko Tamiya's, even if he carried himself a little differently.

"Shinichi." He looked to Migi again. "He isn't a threat. He's not here to hurt anyone. If he was, that girl would have been dead, and you would never have known it was him."

He gritted his teeth, knowing that Migi was right. But he didn't like the fact that Kayoko was living with someone so dangerous. Her life was in danger, and he wasn't sure that there was anything that he could do to help her.

"Hideo Shimada, huh?"


	3. normal

Parasyte -the maxim-  
Symbiosis  
Chapter 3: Normal

Shinichi had known Kayoko since they were kids. They went to elementary school together, and had grown up next door to each other. They were close friends until high school, when Kayoko seemed to drift away. He later learned it was because she started dating an older boy from a different school.

He only ever knew her boyfriend as "Hiroshi," and that was because Murano told him about it after school one day. Murano was worried about Kayoko, as she'd been distant since the two had gotten together. She'd been hanging out with her friends less and less, spending more and more time with Hiroshi. It seemed like Murano was the only one who noticed.

She asked him to talk to Kayoko, knowing that the two were close. Shinichi, of course, agreed, not just because she asked him to, but the way she'd said it made him fear for Kayoko.

Kayoko hadn't told him anything.

She'd simply smiled at him and said that everything was fine.

He knew that she was lying.

Desperate to see what was happening with her, he stayed close, in their circle of friends. He tried to look after her as best as he could, seeing her off after school every day. He couldn't help but worry about his oldest friend. She was like his little sister, and if anything happened to her, he would never forgive himself for not watching out for her.

Then, a little more than halfway through their second year of high school, Kayoko stopped coming to school for a few weeks. Everyone speculated about what had happened to her. There was no announcement and no news, like there would have been if she had died.

But she hadn't even texted any of the girls she was close with, like she usually would if she was sick.

A week after her initial disappearance, she returned, looking haggard, with dark circles under her eyes and her skin paler than it should have been. She wasn't well, and that much was clear. He hated how she looked so sad and tired all the time. The look persisted for another week or so before Shinichi finally told Murano that he would walk her home another time. He needed to look after Kayoko.

Murano understood, like she always did.

"Kayoko," he'd said one day. "Let's go to the park."

She nodded. "Sure, Shinichi."

There had been a lot of talk that followed them that day, speculating what they were talking about, but Murano and the others shot it down as best they could. They had gone to the park without anyone following them, trying to see what was happening between the two old friends.

"What's wrong, Kayoko?" he'd asked as soon as they sat on the swings, just like they had when they were younger. "You looked so tired lately… I can't help but think something's gone wrong."

She hesitated. "Shinichi… you've been seeing the news about those mincemeat murders, right?" He nodded. "About a few weeks ago, my parents went out for their anniversary. They were killed by someone, and… all that's left of them is with the police right now."

For some reason, Kayoko wasn't crying. It may have been because she had run out of tears.

"We don't get the bodies until the police are finished conducting autopsies. It's been a while, since there isn't much to see. The funeral is this weekend. I was going to tell you tomorrow, but I guess you know early." She managed a weak smile. "Sorry I kept it from you," she apologized as she stood, the swing gently swaying from the force.

Shinichi didn't know what to say.

He and his family went to the funeral. They'd told him about it the same day that Kayoko had. His mother had been devastated. His mother, who had died because of the parasites, the same way her parents had.

He knew what it felt like to lose someone that way.

So he couldn't bring himself to understand how Kayoko could accept Shimada, even though she knew that his kind had been the ones to take her parents away from her.

It just didn't make sense.

* * *

Gym class was pleasant for Hideo.

He didn't have to hide his superior abilities. He just had to hold back a little, in fear of making himself stand out too much. It didn't matter, though. He was still faster and stronger than everyone else in the class, even if he was only using a percentage of his true abilities.

Everyone except for Izumi.

Izumi, who stood in front of Hideo with crossed arms as they spoke. Hideo was continuing his attempts to convince the human that he didn't have any intent to harm anyone in the school, and that he was only there out of curiosity about the human race. Izumi wasn't seeing the truth, though. He was still stubbornly seeing Hideo as a threat to his friends.

So, Hideo thought that a little white lie would help things along.

"I haven't harmed any human in recent memory," he said bluntly. "I've been managing to exist on a diet similar to those of humans. Kayoko's cooking is quite enjoyable, especially her… what is it? Hamburg steak?" He paused, seeing how Izumi's face darkened at Kayoko's name. "Something wrong?"

Izumi glared even more strongly. "You have no idea what's happened to Kayoko, do you?" he demanded.

"I do." The parasite frowned. "Your right hand wouldn't know, but when we devour the brain of a living being, we can absorb all its memories and skills. I took over her boyfriend's body, even though what he's done is very unpleasant. But he's been there throughout the entirety of the past year." He looked down at his hands, where his knuckles were still missing some skin from the night that his host had beaten Kayoko. "You're angry because she's accepted me, when one of my kind murdered her parents."

The human made a sound of disapproval. "Of course," he spat.

Hideo sighed, catching the soccer ball he was juggling with his feet. "I see. That's how it is. If that's what you're worried about, just talk to her. She'll be back at school tomorrow." He tossed the soccer ball to Izumi, not wanting to waste any more time with the stubborn boy.

Izumi caught it, purely out of reflex, but never lessened his glare.

* * *

In just one day, Hideo had become one of the most popular boys in the school.

Kayoko stared up at him as they ate lunch together behind the school. "You've got a lot of admirers in just one day," she joked, nudging him. "Mister Popular, huh?" She giggled at his confused face.

"Admirers? Why?"

She raised an eyebrow. "Well, that face is attractive. You look like you could be a model or an actor or something. Some kind of celebrity," she explained.

He still looked confused. "Why would I want to be one of those?"

Sighing, she smiled at him again. "You won't get it, so don't worry about it. Just know that those girls want me gone. They want to be sitting with you." She glanced over to the corner of the school, where a few girls were peering around the wall, glaring at her with jealousy.

Hideo turned, following her gaze. "I don't want any of them to sit with me. None of them are very pleasant. They are all very loud and some of them even smell strongly like chemicals. I'm fine like this," he replied bluntly, his tone bored.

Kayoko laughed a little, knowing that he wasn't trying to be rude. He just didn't understand the way that human girls worked. Even a genius, alien bug had trouble understanding women.

"You men are all the same, no matter what species you are."

He glanced at her in confusion, but she didn't elaborate.

* * *

"Kayoko." She turned to see Shinichi behind her, looking a lot different than when she last saw him. He looked more mature than he had, like he'd aged ten years in only a few months. "Welcome back. It's been a while." He paused, smiling gently at her, the way that he always had. "You look well," he said softly, that kind look in his eyes that he always had.

She returned the smile, shifting on her feet. "You do, too. You started spiking your hair," she commented, pointing towards his hair.

He flushed. Running a hand over his hair, he replied, "I wanted to change it up a little." He looked up at her again, his eyes suddenly serious. "Can we talk for a little? There's something that's been bothering me since I heard you were coming back."

Her eyes widened, fear pricking at her heart. "S-Sure…" she agreed quietly.

The two walked outside, towards the center of the school, where people rarely went at that time of day. She trailed behind Shinichi with concern tugging at her heart, trying to figure out just what he wanted from her, what it was that he wanted to talk about. The only thing that she could possibly think of was that he knew about Hideo somehow, and that was what was bothering him. Her heart jolted at the possibility that Shinichi somehow knew about the parasites.

He stopped, not facing her. She stared at him.

"Hideo Shimada."

Her blood ran cold. She knew that he'd want to talk about Hideo. But what she couldn't figure out was how in the world he'd figured it out. She and Hideo had been so careful when they created his false identity to get him into school.

She shifted slightly, a guilty look on her face. "So, you know then?" she murmured.

"How… how could you…?" his voice was hurt, filled with betrayal. She gazed at him, seeing an unfamiliar look on Shinichi's usually kind face. "You know what he is, Kayoko, but you still stay with him? You let him live under the same roof as you and you feed him, give him a name, and treat him like a human? What's wrong with you?!"

His voice grew louder and louder as his anger boiled over, further and further until he was grabbing Kayoko by the shoulders, pinning her against the wall of the school. His grip was painful, his fingers digging into her shoulders. But still, she didn't look at him.

She could feel tears streaming down her face as she took deep, shaky breaths. "He's not like them. He's Hide, not some mindless monster. He's a good person, Shinichi," she replied quietly, reaching up to wipe her tears away with her sleeve.

Shinichi made a strangled sound in his throat, but backed away. "He's a murderer. They all are," he muttered angrily. "You should know that better than anyone."

"Shinichi." She glared at him, trying to let him know that he'd gone too far. Her tears of frustration had turned into tears of anger. "You don't know him."

"And neither do you."

She shook her head. "Maybe. But I know him more than you. He could've killed me the first night he took over Hiroshi's body. But instead, he helped me." Shinichi stayed quiet. "Hiroshi… he beat me. He beat me so badly that I thought I was going to die. But when Hide came along and killed Hiroshi, he could've killed me, too. And that would've been fine. They would've known it was Hiroshi, and they would've known how bad he was." She hiccupped throughout her words, holding her hands against her heart.

"He… he saved you?"

"He kept me from bleeding onto the kitchen floor. He made sure I was patched up, and he helped me. I trust him, Shinichi. You shouldn't let your own preconceived notions about what they are get in the way of accepting help." She offered a small smile at him.

Shinichi still had it in him to look guilty. He looked down at the ground, at his feet, as he hesitated. His guilt turned to apathy, and he looked at her again, this time without any emotion.

"Do what you want."

Then, he turned, and left her there. She fell to the ground, collapsing on her knees, as she sobbed, mourning the fact that she'd lost another person to the parasites.

* * *

Hideo quickly realized that something was wrong with Kayoko. She'd been unhappy the entire day, and the spark of life she'd had as they walked to school together had disappeared, replaced with a cold void of nothingness.

"Kayoko… did something happen?" he asked over dinner.

She shook her head. "No. Just had a talk with someone I thought was my friend." She paused, then glanced at him. "Shinichi doesn't seem to trust you. Why is that?" she asked.

He frowned. He had known that Izumi didn't trust him, but he didn't think that Izumi would have it in him to make someone he cared about feel so sad.

"It's because I'm not human," he finally said. "He's unfortunate in the sense that he's trapped between two worlds – ours and yours. His right arm is like me. The rest is like you." He didn't want to hide it from her. She deserved an explanation.

She sighed, but nodded. "Okay. I get it. He sees you and your kind differently. Bad things must've happened to him… I hope he's okay," she said to herself.

Hideo didn't understand how she could still have the capacity to care. Even after someone had made her cry, she still cared about that person enough to be concerned with their well-being. Most humans would be angry and hurt, but not Kayoko.

Perhaps that was what made her so special.

* * *

Yuko Tachikawa liked Hideo Shimada.

Which meant that she was jealous of one of her best friends, Kayoko Kenzaki.

Kayoko seemed to know Hideo very well, and the two were close. They were in the same class, and Hideo rarely ever seemed to leave her side after the first day Kayoko returned. He and Izumi were at odds for some reason, but Hideo only ever seemed to become hostile when Kayoko was near Izumi, while Izumi was hostile almost consistently.

She'd noticed how Hideo seemed to dislike conflict. He'd only displayed some form of violence once, and that was against some trouble-maker that she'd seen messing with Izumi a few times. She figured that he must have been threatening Hideo.

Or Kayoko.

She didn't understand what was so special about Kayoko. She didn't understand what kind of secret they shared to bring them together.

She didn't understand why it couldn't be her.

Yuko Tachikawa never hated anyone. She couldn't hate Kayoko, especially after everything that she'd gone through. But Yuko Tachikawa was jealous.

She liked Hideo a lot.


	4. affection

Parasyte -the maxim-  
Symbiosis  
Chapter 4: Affection

Hideo stared at Kayoko in shock. He was, for the first time, feeling something other than nothing. He couldn't fathom what he'd just heard from her.

"What?"

Maybe he was hearing things.

"I know you've been killing girls, Hide. You can change your face to lure them in. You're a bad liar, you know." She smiled weakly at him. "If you need to eat human flesh so badly, don't you think it'd be better if I died than you killing random people?"

He wasn't hearing things.

He frowned, not liking the idea at all. It repulsed him, actually. "No. That wouldn't make anything better. Because I wouldn't like to see you get hurt." He paused, then repeated what he'd been saying for ages. "It's not right for you to die."

Her eyes widened. "Hide…" she managed, but he cut her off with a dark look.

"Don't bring up the subject again. I'd rather you hate me for killing people than hear you suggest that I kill you instead."

* * *

Yuko somehow knew now.

She knew, in her gut, that Hideo Shimada was one of the things that her brother was investigating.

Akiho had been joking when she suggested that Hideo's face was fake, but it stirred a thought in Yuko's mind. She saw the sketch that her brother had done for his investigation. She heard what he'd said about the _things_ that were killing people.

Everything made sense. Hideo had to be one of the things that her brother was looking for. It was the only solution.

But she couldn't quite figure out how Kayoko fit into his plans.

If she even did.

* * *

Hideo sat next to Kayoko, sitting up straight and proper, while she held a pillow to her chest, snacking on some of her favorite chips. His eyes were only half on the movie that they were watching. Something about a man with wings and a girl who was cursed to become old. It was "anime," or so Kayoko called it.

"It's my favorite," she'd claimed, showing him the DVD case proudly. "Can we watch it?"

She seemed happy. Her eyes were no longer lifeless, like they had been after Shinichi completely trampled her feelings. They were twinkling at the mere prospect of being able to watch her favorite movie with him. Of course he agreed. It was only right that she was shining like that.

Every so often, she pointed at the screen, explaining certain plot points to him. She somehow knew what he wouldn't understand, such as the parts that had to do with the war and magic.

"Humans are so fragile," he muttered as he watched the main girl try to save the man she was in love with, walking through time in order to do so. "They become so blinded by love that they don't realize the consequences of their actions."

Kayoko glanced up at him. "Love makes people do crazy things," she murmured.

"I wouldn't know." He met her gaze. "My kind… we don't have the ability to love the way that humans do. I can't feel the same emotions that you do."

She frowned, her hand moving to rest on top of his. "Sure you can, Hide." She managed a small smile at him, her attempt to reassure him of things that he knew were false. "You're just like a human. Your kind can't be so different, can they?"

"Kayoko, my kind is responsible for the deaths of hundreds of people." She flinched. It didn't escape his notice. "You lost people to the violence of my kind, too, didn't you?" Her eyes suddenly turned towards the floor.

Taking a deep, shuddering breath, she nodded. Her hand found its way to hold his, her fingers weaving between his as she held it. She was shaking.

"One of your kind killed my parents. They were turned into food for one of your kind," she admitted softly, tears welling up in her eyes. "The police told us that we should have a closed casket funeral. There wasn't enough of them to have an open casket."

Hideo did the only thing he knew would work. He tightened his grip on her hand.

She looked at him, a small smile forming through her tears. "It's okay, though. A lot of good things have happened, even from all these bad things," she said quietly.

"How can you be so positive?" he asked softly. "Your boyfriend, who was supposed to love you, beat you instead. Your parents, who were supposed to watch you grow up, were stolen from you by one of my kind. I don't understand how you still have the capacity to care so much about others… and especially about me. After all I've done, after all my kind has done, you still care about me. Why?"

Kayoko hesitated for a moment, sitting up straight. She ran her thumb over the back of his hand. "Well, people do bad things all the time, but we don't condemn all of humanity for the actions of a few." She smiled softly, feeling his skin under hers. "This body may have belonged to someone who hurt me, but you're the one who's here now. You, who decided not to kill me, even though you could have. You, who let me live with you, even though I'm sure you could survive on your own. You. Hideo Shimada. Even if you're not human, you're a better man than… than Hiroshi ever could've hoped to be." She sighed happily, her grip on his hand not loosening.

He looked down at her. He felt something stirring in his gut, and it was something that he couldn't quite identify. It was an unfamiliar something that he'd never felt before.

 _Felt._

His mind quickly scanned through the possibilities. It wasn't a negative feeling, that much was certain. It wasn't fear or anger. It wasn't hatred or bloodlust. It wasn't any of those things, the feelings that Kayoko would call "ugly feelings," because she claimed that feeling those things and holding onto them would cause them to leave a scar on the heart.

It was a positive emotion. Something that wasn't ugly. It wouldn't leave a scar on his heart if he held onto it, so he thought that maybe, he could keep it for a while.

He finally settled on the feelings of "pride" and "affection."

Pride for the fact that he'd kept Kayoko from dying at the hands of her abusive boyfriend and for the fact that he'd been the one to keep her from believing that all of his kind were as bad as the one that had killed her parents, even if that only applied to him.

Affection for the way Kayoko was. She was quiet, weak, and cowardly, shying away from any situations she deemed dangerous, but she was, maybe, braver than even Izumi. She could face her fears if she thought it was safe, and even trust other people, even if she was to be hurt. Humans were never very good at facing things that scared them, but Kayoko…

Kayoko smiled at him, an inhuman creature that was created for the sole purpose of survival, even if that meant killing humans in order to survive.

She smiled at him like he was _human_.

He felt something fall onto his shoulder. He looked down to see the dark-haired girl's head resting against his shoulder, her eyes closed as she breathed in and out. She looked content, even with the talk that they'd just had. Her hand still clung to his.

Her hand, which was small and delicate compared to his. His hand engulfed hers in its grip. It was just like her – fragile compared to him. But he didn't mind being the stronger one.

He could protect her if he was strong enough.

Sighing, he let his head fall back against the wall. She may have thought that he was a good person and, in her eyes, he might have been. But it didn't stop the fact that he'd hurt other people – not her – in order to keep his strength up.

"Should I stop killing?" he mumbled. "Would that make you happy?"

She didn't answer, but maybe that was for the best. Whatever she said would make his decision for him.

This was something he had to decide on his own.

* * *

Kayoko raced down the street, away from the school. She'd heard from Akiho that Hide had been called out by a group of older boys, some gang that had been harassing students from the school – including Shinichi – for the past few months.

She'd left her bag behind as she ran towards where the boys in her class said that they took their victims to fight them. She stumbled a few times, her weak body nearly failing her as she prayed that they wouldn't try to fight Hide before she got there. If she was there, she was sure that she could talk him down, but if she wasn't…

… it was sure to be a slaughter.

She panted as she turned the corner, skidding to a halt.

Hide stood near Shinichi, blocked from her path by a group of tall, intimidating boys. She bit her lip, hesitating because of the situation she'd just run into, but she knew that everyone else in the vicinity was in danger if they threatened him.

"Hide!" she cried, catching the attention of the boys. They all turned to look at her, even Shinichi, all of them showing the same shock on their faces. "Hide, what're you doing?!"

He was calm as he pushed past the boys, picking up the bag he'd discarded near the entrance to the lot. "I was telling them that they shouldn't pick fights that they can't win." He glanced towards the boys, his eyes radiating hostility. "And that if they try, they should be prepared for me to end them."

Kayoko frowned, seeing the hatred in his eyes. "I know you're stronger than all of them put together, but you shouldn't fight them. If you got serious, you could kill them. Please… don't hurt them. They're just dumb boys. They don't know any better," she murmured quickly, so only he could hear her.

Looking down at her, he nodded. "I understand. I wasn't going to go all out, anyways." He held up his hand, clenching it into a fist, as if that demonstrated the immeasurable power she knew he had. "It'd only take a portion of my strength to knock them all off their feet."

"Just promise me that you won't get into any stupid fights."

She held out her pinky, pouting childishly. Hide sighed, but nodded once more, holding out his pinky before interlocking it with hers. After a moment, he pulled away, offering his hand to her. She took it, a happier, calmer look on her face.

He turned back for a moment. "Izumi. I wasn't about to hurt them. At least, not too badly." He smirked, letting his words sink in for a moment before he pulled Kayoko away.

"Hey, Hide, wait! I left my bag at school!"

* * *

Shinichi cursed his strength and his hatred. He'd already managed to push away Kayoko after she tried to convince him that Shimada wasn't as bad as he seemed. He'd scared Murano even more as Shimada tried to talk to him, his survival instincts causing him to hurt her, even if it was just by accident.

He couldn't help but remember how Shimada and Kayoko had seemed so close, so comfortable with each other, as they faced off in front of the school.

She'd stood close to the parasite, practically hiding behind him. As if he'd noticed it, Shimada had shifted underneath Shinichi's glare, moving to block Kayoko from his sight. She'd shrunk even further behind him as he did. As Shinichi had yelled, losing his temper with Shimada and his speculations, Kayoko had latched onto Shimada's arm.

At first, Shimada looked as if he'd wanted to fight Shinichi. But after she whispered something in his ear, he'd backed off. He'd turned away without even a single jolt of hostility leaking from him.

"Migi," Shinichi began, glancing at his right hand, "do you remember what Shimada was feeling? What kind of signal he was radiating today?"

Migi opened his eye, staring at his host. He blinked. "Of course. He was mostly calm today, even during the time when he was being threatened by those humans. The only two times he spiked were when that girl appeared at the lot and when you raised your voice at him." He paused, then added, "But only the latter of the two was when Shimada showed any signs of hostility. The first incident was something else entirely. I'm unsure of what it was." He blinked, his lips frowning a little.

Scoffing, Shinichi fell back on his bed. "So, he gave off some sort of signal that you can't identify?" he muttered, glaring at the ceiling rather than at Migi. All of his focus was going to dissecting the enigma that was the parasite named Hideo Shimada. Shinichi just couldn't figure out his motivations.

"I can make a guess," Migi suddenly interjected. "From what I know of emotion, Shimada was radiating something that you would call 'worry.'"

Shinichi's eyes widened. "Worry? Why?"

"I can only assume it was because the girl interjected herself into a possibly dangerous situation," replied Migi easily.

Biting his lip, the human of the two moved his gaze back to the ceiling. He took a deep breath, thinking back to how Shimada had acted when Kayoko got involved.

"Worry, huh…?"

* * *

Hideo took a look at his hands. They were stained with the blood of a girl he had killed. He didn't even know her name. He just knew that she was an easy target. She was quiet, unsuspecting. She was probably a tourist who'd been lost in the city. No one would notice that she didn't come back with him.

But Hideo would know. He knew that he'd just hurt a human being again. He'd done it for himself, to sustain himself. And somehow, that repulsed him.

Sighing, he walked to the nearest public bathroom, staring at his reflection for a moment, seeing the blood splattered across his cheek. He turned on the faucet and let the blood run down the drain. As he did, he looked into the mirror, seeing his own blank eyes staring right back at him, like they were taunting him.

 _"_ _What if Kayoko knew?"_ his reflection asked, taunting him with those blank eyes. _"Wouldn't she hate you? Wouldn't she cry? She told you today. She stopped you from killing those boys."_

"Shut up."

 _"_ _You're a liar, Hideo Shimada. You don't deserve the name she gave you. You lied to her. If she knew, she'd never look at you the same."_

"Shut _up_."

 _"_ _She'll never trust you again. After all, she'll know that you could kill her, too. She'll know that you're just like the thing that killed her parents. A_ _ **murderer**_ _."_

"Shut _up!_ " Hideo roared, feeling anger overtake him, much to his shock and horror. He found himself slamming his fist into the mirror, shattering it with all the strength that he had. He panted, seeing the blood run down his fingers, dripping onto the tiles beneath him.

This time, it was his own blood.

He backed up, against the walls of the bathroom. He slumped to the floor, watching as the red, human blood trickled down his palm. He bled just like she did. Her blood was red like this, too.

"Sorry, Kayoko," he muttered. "I'll stop now."


	5. control

Parasyte -the maxim-  
Symbiosis  
Chapter 5: Control

Yuko had all the evidence she needed.

She'd witnessed how his head had been dented by a baseball, but only seconds later, it'd reverted to its original shape, without any dent in sight. He hadn't even flinched when the ball hit him, when most people would have collapsed from the pain or the shock. He'd simply turned around with blank, _dead_ eyes that seemed to say more than she could have learned if she'd just asked him.

She'd seen it with her own eyes. His inhumanity.

She'd watched his face turn into something different, a new face that mimicked one in a poster on the side of a building. Someone that she didn't recognize, and it certainly wasn't his. It wasn't the face that she'd seen in school every day. It was that of a celebrity. He'd gone from being someone she was used to seeing to someone who she'd never met before.

With all that she'd seen, she came to a conclusion.

There was no way that Hideo Shimada was human.

* * *

She'd been in the bathroom all morning. She'd gotten up quietly and gone to the bathroom early that morning, before she should have been awake. He could hear noises that sounded like she was vomiting, retching with awful coughing sounds. He flinched every time, but didn't move until his alarm sounded.

"Hide." He looked up from where he was packing his school bag. Kayoko, who looked extra tired, ran a hand through her hair. She had a hand wrapped around her stomach as she emerged from the bathroom. "I think I'm getting sick again. I feel awful."

He frowned, putting his hand against her forehead. "You don't feel warm."

"Maybe we should stay home today… I feel like something bad might happen," she admitted quietly. "It sounds dumb, but I just… I'm worried." She bit her lip, looking down, away from him.

Hideo gently moved his hand to rest against her cheek, causing her to look up at him. Her eyes were wide and her face was red. He could even hear her heart skip a few beats, like she was sick, but he chose not to comment on it. Instead, he gazed at her with strong, determined eyes.

"As long as I'm with you, I'll make sure nothing happens. And if I have to leave you for some reason, I'll only do so when I know you'll be safe. I promise that I won't let anything happen to you," he vowed, sounding as strong as he could.

She needed him to be strong, especially when she was such a weak, sickly girl. She was weak even for humans, who were already weak enough. But she was especially vulnerable. She would be the one in the most danger if anything were to happen. For example, if Izumi's right hand decided to go rogue, it could possibly kill her first, considering that she knew exactly what the parasites were.

For all intents and purposes, she was a danger to his kind.

But he still promised her that nothing would happen. He promised that he wouldn't let anything happen to her as long as he was standing.

She smiled wryly at him. "You can't control everything, Hide," she murmured.

"No. But I can try."

* * *

Yuko called Hideo to the Fine Arts room, a small classroom hidden away in a wing that barely anyone ever went in the mornings. She'd slipped a note in his shoe locker, asking him to come.

She didn't expect him to show up.

But when he did, the first words out of his mouth were, "What is it? Don't take too long. I have to get back to the classroom."

The girl had to summon all her bravery. If she was wrong, she'd ruined her chances with the boy that she liked. But if she was right, her life was in a lot of danger. Either way, something bad was going to happen in the next few moments.

"I know you probably never noticed me, but I noticed you from the beginning," she began, her voice shaking. "I always noticed you. And… I noticed." She trailed off for a moment, trying to collect herself. "I don't like thinking that you're different, but if you're what the rumors say… if you're something that kills and eats humans…" She didn't know how to continue, so she simply trailed off.

"If I am?" he asked slowly from behind her.

Yuko bit her lip, hesitating for the briefest of moments. "If you are… I want you to leave. I want you to leave and never come back here," she demanded, curling her shaking hands into shaking fists.

It was a weak demand.

But Yuko wasn't a strong person.

She wasn't bold like Akiho. She could never speak her mind like Satomi. And she could never bravely face her fears like Kayoko. She wasn't like any of them. But she was smart. She was good at finding the truth, even if it was hidden under layers upon layers of lies.

This was her strength, and she had to handle this herself.

"I don't want you to kill anyone!"

* * *

Hideo's eyes went wide.

 _"_ _Even if you're not human, you're a better man than… than Hiroshi ever could've hoped to be."_

It hadn't even been a week since Kayoko spoke those words to him. It had only been a few hours since he resolved to never kill or harm another human. It'd only been a few minutes since the only person, besides Izumi, who knew what he was smiled at him.

And now, this girl threatened to take away all of that.

He looked down. "Did you tell anyone what you found?" he asked slowly.

She didn't answer his question. "Do you really kill people?" She replied with her own.

For a moment, Hideo paused, as if he was debating answering her at all. "I used to. But I decided recently that I wouldn't anymore." He looked at the short-haired girl coldly, his gaze piercing her as he spoke. "I figured it'd make Kayoko sad. She hates the idea of me hurting anyone. So, in favor of me not hurting you, answer me… did you tell anyone else?"

"No, I didn't," she replied shakily, her eyes widening as she took tentative steps back. "But, Shimada, are you saying… are you saying that Kayoko knew… all along?"

 _Not good._

"How could she… She knew? She knew what you were… and she didn't say anything? She got close to you like that and-and… and she let you live without telling anyone? How… how is that… Is she… even human?"

Hideo's eyes narrowed into a glare. His face darkened completely, his apathetic, emotionless expression from only moments prior completely gone. He aimed his glare at the girl, who shivered under his dark look. He could feel something negative bubbling up inside him.

 _Hate. Anger._

 _You hate her. You're angry at her._

 ** _Kill her._**

His instincts told him that in order for him to survive, the girl needed to die. She knew too much about him, about his kind. She was a danger to his way of life. Yet something else entirely told her that what she was saying about Kayoko was unacceptable. What she was saying about Kayoko was bad. It was wrong. She didn't need to die because she was a threat. She needed to die to atone for the horrible thoughts she had about Kayoko.

This girl in front of him didn't deserve to live.

"Why are you talking about her that way?" he demanded softly, his voice quiet, but carrying all his anger.

The girl backed up a little, her entire body shaking. She was afraid, just like human beings would be. They should all fear him. "Be-because! She knew, and she didn't say anything! How could she side with something that kills and eats humans?" The girl's eyes darted around, searching for an escape route.

"Because she is better than the rest of you. She sees our similarities, not our differences." He advanced, causing her to shrink back even further. "Will you be telling anyone about this?"

She shook even more, and Hideo knew. She would tell everyone if he let her walk away. If he let her go, if she told, his life as he knew it would be over. He would be captured or killed, taken to be experimented on. Either way, he'd be taken away from the only human who was worth protecting.

 _They're all the same… I thought there would be others like her. I thought we could coexist. Tamura said… that it was possible. But their response to fear is hatred, anger, and violence. We cannot live in harmony._

He couldn't allow them to take him from her.

His face split apart in an instant, his skin turning into the blades that had taken the lives of many before her. His blades were sharp enough to kill her, and he knew it. He would not allow her to live, not after what she said. Not after what she could possibly do. He couldn't allow any of it. Not a single thing.

As she struggled to find breath to even scream, Hideo struck.

He barely missed. She'd managed to gather herself just in time to dodge his strikes. He cursed his slow reaction time. He wasn't used to having his targets resist him. In the time it mattered most, his natural abilities as a killer were failing him.

But her dodge caused her to fall to the floor. He advanced, knowing that there was no way that she could escape him. As he raised his blade, preparing to deliver the final blow, she tossed something at him, high into the air.

He struck whatever it was with his blade, hearing glass shatter above him, but something poured down upon him. Liquid seeped into his skin, burning the soft tissue like it was paper. Whatever it was, it was like acid to him, and he couldn't help his shriek of pain as it hit his most sensitive skin. His true self curled into a ball, not knowing what to do. It didn't know how to react to this liquid that was killing his cells, forcing him back from his own body.

It was like he was having an out of body experience.

All he could hear were his own thoughts. They were screaming at him in pain and desperation, but he couldn't force himself to respond. The pain was too much for him to bear.

 _Hurts_ was the only word that he could muster.

His body was not his own. He couldn't control what he was doing. Something about that liquid had cut off his mind from his body, separated the rational side from the animal. He wanted to force his face to return to its human state, but it wouldn't listen to him.

Instead, the blades shot out the window, following the annoying girl who had burned him. They struck blindly, trying to pierce her, slice her, _kill_ her. His body wanted her dead, even though his mind just wanted to gather itself.

He was not one whole being anymore.

He was fragmented.

He was not in control.

* * *

Kayoko's eyes were trained on the classroom door. Her hands were clasped together over her lap. She was barely listening to the teacher as she stared at the door, hoping that Hideo would come back through it. He'd been missing since before class started.

"Hey, Kayoko," Satomi whispered to her. Eyes wide, she looked to her friend. "You're distracted. Are you okay?"

Biting her lip, she hesitated. Satomi deserved to know, especially since Shinichi was bound to get involved if Hideo was in trouble. But she deserved to hear it from Shinichi, not from Kayoko.

She shook her head. "No. Just worried about Hide," she replied.

Satomi's face softened into a smile. She giggled, her eyes crinkling in a smile. "You really love Shimada, don't you?" Her words pierced Kayoko, whose eyes went even wider and face flushed a deep, dark red.

She looked down at her book, where she'd copied down whatever was on the board on two separate pages. One was for Hideo, so he could review whatever he missed when he returned. She'd thought of him, even if she didn't realize that she was. She'd put him as a priority, even though she wasn't paying much attention to the class.

"I guess… I guess I do."

* * *

 _Return to normal. Find Kayoko. Get her. Get out._

Those were the only thoughts that Hideo could understand, and they were the only goals he wanted to accomplish. He needed to get out of the school, maybe out of the town. He needed to leave, before that girl could tell the authorities what he was and before they could find him.

 _I don't want to die._

When had his thoughts turned to death? When had it become so important for him not to die? When had living become his priority?

When had he become so… _human_?

Kayoko would assure him that "it's not a bad thing" if he told her his thoughts. She would tell him that feeling human wasn't bad. She would tell him that it was good, because it meant that they weren't so different after all.

 _I don't want to die here._

Not like this.

He wanted to live just a little longer.

If he needed to run, he would. He could live on the run. He could survive as long as he needed to.

 _Kayoko._

He struggled along, trying to force his true self back, trying to bring his human face forwards so he could at least seem somewhat normal.

 _Go to class 3… She's there._

This thought travelled throughout his body, forcing his feet along. It seemed like the only thing that unified his disjointed thoughts was the idea of seeing her again. She was the only thing that mattered to his broken, fragmented self. He needed to be in control, but he wasn't the one who currently was.

She was the one who controlled him.

He smirked internally at this realization. Perhaps she had always controlled him, and perhaps that was why he didn't think much of his slow transformation. He'd become less and less like his kind and more and more like her.

His kind may have been ahead in strength and intelligence, but for some reason, he was always running to catch up to her.

She was three steps ahead of him. She would always stop, look back, and wait for him to catch up, but whenever he did, she took another three steps, and was ahead of him again. No matter how long she waited, he would never be able to be on the same wavelength as her, but he could at least try.

He had been trying, unconsciously. He'd forced himself to unlock the parts of him that his kind had sealed away. The parts that his kind had deemed as weaknesses. The parts that she saw as strengths.

Emotions. Happiness. Remorse. Sympathy. Forgiveness. Trust.

Love.

 _"_ _Love makes people do crazy things."_

He was doing something crazy right now. He was abandoning something that his own kind had told him to do. He was abandoning his life as he knew it for safety. But he didn't want to abandon her.

He could have just run the instant that the girl revealed what she knew. Instead, he tried to reason with her. He tried to explain things in the way that Kayoko had explained them to him. He tried to make her see that he was different than the rest of his kind.

 _"_ _You're just like a human. Your kind can't be so different, can they?"_

That was what she was trying to tell him that day.

They were more alike than they were different. If his kind only opened themselves up a little bit more, let themselves feel the way humans did, then perhaps they truly could coexist. Perhaps they could find harmony together. If his kind wanted to, they could practically become human. They could stop feasting on human flesh and start eating the way that humans did.

If only.


	6. blood

Parasyte -the maxim-  
Symbiosis  
Chapter 6: Blood

There were screams in the hallways.

Kayoko was frozen in fear, knowing that something happened involving one of two people. Shinichi Izumi or Hideo Shimada. One of them had lost control of their killer instincts, and had struck.

There was bound to be blood spilt.

She shook in her seat. She was the only one in class 3 who knew what was happening. She was the only one who was part of the raging war that went on outside, the war that no one else in her class even knew existed. She was the only one who should have been involved.

Stealthily opening her phone as the class, she dialed the number on Hideo's prepaid phone, the one he rarely used. The call failed almost immediately, much to Kayoko's horror. Snapping her phone shut, she looked around the room, desperately hoping that Hideo would magically turn up.

He wasn't anywhere to be found.

Standing on shaky legs upon this realization, she ignored the questioning calls of her name from both Satomi and her teacher as she moved towards the doors. "I have to find him," she muttered to herself, clenching her hands into fists.

Before anyone could stop her, Kayoko ran off. She flung the classroom door open, running down the halls. She knew that if she just followed the screams, they would lead her somewhere. Maybe to the one who was causing all of this.

She just hoped that it wasn't Hideo.

She didn't want him to turn into something he would hate later.

* * *

Hideo tried to scream for his body to stop. He tried to yell for it to not do what it was doing. He didn't want to feel the blood on his blades, and he didn't want to hear the gurgling of the dying humans around him. He didn't want to realize that he'd killed another human in his own madness. He didn't want to feel that painful jolt as he sensed the end of a life. He didn't want any of this.

He needed to get to class 3. That was all he wanted.

These humans were just getting in his way. He wanted to just brush past them, since they couldn't hurt him, even if they tried, but for some reason, his body wouldn't allow that. His body wanted to kill them. His body wanted to see them drop to the floor and writhe in pain as he ripped them apart. So, that's what his body did.

He hated it.

He felt less human than he ever had.

Inside, he was screaming for someone to stop him. He felt self-hatred. He felt useless. He felt like a murderer. He didn't like any of these feelings, and wanted them to go away. He wanted to return to questioning what it meant to be a good person. He wanted to go back to pondering his own humanity, the way he had before the blood started flowing.

He wanted Kayoko.

 _Don't hurt them… just get Kayoko and run,_ he pleaded with his body. _She'll never forgive me for this. I just want to live._

His body paid him no mind. It continued to slaughter anything that got in its way. Inside his own mind, Hideo flinched, seeing the blood splatter all over the walls and the floors, seeing the bodies that were scattered around the hallways.

 _I… I'm sorry. I didn't want this._

* * *

Shinichi looked around the evacuated students. He didn't see Murano or Kayoko anywhere within the crowd. Worry built up in his heart as he continued to search, hoping to catch even one glimpse of the girls. But they never showed up in his vision.

"None of the class 3 students evacuated… Something must've happened."

As soon as he heard those words, Shinichi knew.

He dashed back into the school through an open window, rushing through the hallways as Migi pointed him in the right direction.

Screams caught his attention. He looked out the hallway windows to see some of the class 3 students he recognized running out the door. Many of them were crying, and some had blood on them. He gaped, seeing the expressions on their faces.

 _Shimada… went after class 3…_

As the students continued to run, Shinichi stared, waiting for the two familiar girls to emerge from the school. Neither of them did.

"Neither of them are here," he muttered, worry in his voice.

Migi looked up at him. "He's still on the third floor." He didn't tell Shinichi anything else. There may not have been anyone else left alive.

Maybe it was better that Migi stayed quiet.

* * *

Kayoko found herself running back towards her classroom. She had searched the entire school, but he always seemed to be ahead of her. The screams led her to her class, on the third floor.

Upon reaching her class, she suddenly wished that she hadn't. She could feel bile in the back of her throat as she clasped her hands over her mouth. Her classroom and the hallway before it had been dyed a deep crimson, bodies leaking blood all over the school. They all belonged to people she'd joked around with for the past few weeks. They were people she knew.

 _Ueno… Yuki… Ishida… Rei… Ogami… Fuji…_

She listed off their names in her head as she carefully stepped through the blood, the liquid sticking to the soles of her school slippers. She said a quiet prayer as she passed the people she knew. They were all good people. Young and stupid, yes, but they were good. They didn't deserve to die like this.

"Hide… what happened to you?" she whispered, dread filling her senses.

The dead had looks of fear and panic frozen on their faces. The last thing they'd seen had scared them into sobbing, probably begging for their lives or screaming in terror.

She took a deep breath, steeling her heart. She had to be prepared for whatever it was that she found, even if what she found was no longer the Hide she knew. As she continued walking, a small voice called out.

"Kayoko?"

Freezing in place, she turned.

In a small hallway, one that was cornered off from the rest of the hall, sat Satomi and Shinichi. She was curled away in his arms, tears flowing freely down her face as she clung to him desperately. He was trying his best to comfort her, but he simply couldn't bring himself to bring her closer, not when he knew that what had killed her friends was the same thing that resided in his right hand.

When he saw Kayoko, his gaze hardened. "Did you know?" he demanded.

She managed the weakest smile that she'd ever shown anyone. Her insides hurt and her eyes burned. She choked as she shook her head. "I didn't know what happened to him. He was fine before school… I don't know… I don't…" She trailed off, muttering nonsense under her breath.

If Hide was there, he'd tell her "breathe" in that calm, quiet voice of his and put his hand on her back. He'd stay with her until she calmed down, until her tears went away.

He'd know what she needed.

"Kayoko…"

She could hear Satomi's voice, broken and scared, but she didn't want to reply. Satomi had been crying because of what Hide did. Shinichi hated her because of what Hide did. Everything they'd worked so hard to keep secret had gone to waste.

"Yuko," she finally managed. "Hide went to see Yuko this morning. She left him a note, saying that she wanted to talk to him about something." She choked on her tears again, biting her lip. "I knew I should've kept him in class. He said he'd be fine. He promised he'd come back." She sobbed. "I shouldn't have let him come today. I told him something… something bad was going to happen."

She felt two arms wrap around her, and she looked up to see Satomi, who had pulled away from Shinichi. "This isn't your fault," she said firmly. "Nothing could have prevented this. You can't control everything."

Nearly laughing at hearing her own words thrown back at her, Kayoko shook her head. "You're right." She pulled away from her friend's embrace. "But I can try," she finished, a sad smile forming on her lips. She looked to Shinichi. "Get Satomi out of here. And promise me that you'll let me try to handle this," she requested, offering him the only smile that she could.

Shinichi hesitated, but nodded. "Don't die," was all he said in return.

She didn't reply to him, just smiled softly. She turned away, crossing her arms over her stomach. Her insides still churned as she slowly made her way towards the stairs. Her breaths were long and shaky, her eyes trained only on what was ahead of her.

She didn't want to die, but she didn't want anyone else to, either.

Stopping Hideo was all that mattered.

* * *

"Where's Kenzaki?!" demanded one of the teachers. "You said she ran off, right?! Did you find her?!"

Shinichi paused, feeling Murano freeze under his hand. She shook her head, her body beginning to shake. "She's alive," she muttered. "But I don't know for how long. She's… she's still in there." Her voice was weak, sad, like she had already come to terms with the idea that Kayoko was dead.

He frowned, feeling guilt in his heart.

Kayoko was going to die. Shimada was going to murder her without even thinking. He swore that he'd never harm Kayoko, but if Migi was right and Shimada was somehow becoming unhinged, then there was really no way to stop him.

He'd been so cold to her the last few times they spoke.

And now, he'd never get to see her again.

Biting his lip, Shinichi cursed himself. He cursed the way that he'd pushed her away over something that now seemed insignificant compared to the idea of her as a human being. She was his oldest friend, someone he'd cared about deeply. He knew that she hadn't changed in the time she'd been gone, or even the time that he hadn't been looking. She was still the kind, trusting, naïve girl that she'd always been.

He was the one who had changed. And as he changed, he'd changed their relationship. All because he couldn't accept that Kayoko placed her trust in someone he didn't like, someone he'd deemed a danger to everyone around him.

Of course, he was right in the end, and that would be the death of her.

But Shinichi couldn't help but feel regret, remorse, and guilt in his gut. If he'd done more, stayed closer to her, this could have been prevented. If he hadn't pushed her away, he could have pulled her out of the school along with Murano.

If he hadn't pushed her away, she would still be alive.

* * *

The police officers were swarming towards him, even as he cut them down. He could feel himself bleeding from where they shot him, but he managed to protect his heart. He still had a chance to live, as long as he could reform himself, become human again.

 _I want to live._

Kayoko wasn't in class 3. She wasn't there when he'd gone there, when he'd massacred his classmates, the people who'd been so kind and open to him when he'd transferred in. He hadn't wanted to. He just wanted to find her, but his body had tried to defend itself when the students tried to attack him.

He couldn't help it.

 _I have to live._

He couldn't die here.

Hideo pushed forwards, past the officers as he cut them down, hearing their bodies drop and feeling their blood splatter across his skin. He let his body do as it wanted. It wasn't just about killing anymore. It was about survival, and Hideo needed to survive. He had to find Kayoko.

He had to know something.

The stairs were tall. There were a lot of them. He panted as he climbed the stairs, holding onto the railing so he wouldn't fall. He knew that he'd lost a lot of blood, probably more than most humans could risk losing. He knew that dying of his gunshot wounds was a possibility that he had to come to terms with.

He just didn't want to accept dying as part of the ending. His death wasn't something that he could just accept. Not when he hadn't found her yet.

Pushing open the door, he stepped out into the sunlight that beamed down on him, warming his body as he limped forwards, blood leaking from his wounds. It was much brighter outside than it was inside. He could feel his entire body relaxing, knowing that it was still daytime. He looked back down the stairs, knowing that there was enough bloodshed to shock a thousand people.

It wasn't his fault.

He didn't mean to do it.

It just… happened.

And now, everything was crumbling down around him.

 _I need to live._

He was just beginning to feel. He was learning what it meant to be human, and not just believing the definition he'd created solely off of the observations he made as an immature being. Even though he was superior, he was not always right.

He'd thought humans were weak and cowardly by nature and, to some extent, he was right. But they'd also proven that they were resilient in the face of danger. They stood up to anything that threatened their survival as a species, they tried to discover weaknesses and fight back, and they tried to figure out what was best so that they could live, and not just survive.

They taught each other how to enjoy the lives they were given, even if it meant being unhappy in some other way.

The way Kayoko taught him.

 _I cannot die like this._

He steeled himself, preparing to defend himself against whatever would come for him next. He had to strike back, even as disjointed as he was. He couldn't let his weakness get the best of him.

He reached up, trying to rub away the dead cells with the sleeve of his uniform, forcing the new, living cells to take their places. He needed to regenerate as quickly as he could, or else he wouldn't be able to stop.

He needed to be Hideo Shimada _and_ he needed to be the inhuman creature he was feared as.

Footsteps echoed up the stairs, these ones lighter and faster than those of the officers. Preparing himself to strike, Hideo raised his blade, forcing it as best he could with his weakened body.

A figure appeared at the door.

"Hide!"

He struck without thinking.

 _Stop!_ his mind shrieked as it recognized that voice.

There was a sickening thump when his blade barely kept itself from slicing the person in two.

Hideo backed away, pulling his blade from the figure. He shook in horror at what he had done.

Blood spread across a navy blue uniform jacket. Small, fragile hands pressed against the wound as weak legs buckled, failing after only a few moments.

"Hide…"

"I… I didn't mean to…"

He didn't mean to strike the only person who ever made any sense to him.

"Kayoko…"


	7. alive

Parasyte -the maxim-  
Symbiosis  
Chapter 7: Alive

The news called his kind "monsters." Everyone called him a "monster" that day. From the girl who had caused all of this to his classmates who he thought had known him to the police officers who only saw the bloodshed he'd caused.

He'd heard it so much that he was starting to believe it.

* * *

"Kayoko!" Hideo rushed forwards, pushing his broken and bleeding body. He caught her before she could topple forwards, cradling her in his own wounded arms. "Kayoko… I didn't mean to…" he sputtered, trying to contain his hatred for himself.

He'd hurt her.

He'd sworn that he'd never hurt her.

She looked up at him weakly. "I'm okay. I've been through worse," she lied. She said that he was a bad liar, but she was just as bad, if not worse.

"You're bleeding."

It was obvious, but he couldn't help it.

He was still trying to understand what he'd done. He had pierced her without even thinking about it, and now, she was lying in his arms, bleeding.

Emotions stirred within him. He struggled to place them, only half noting that feeling meant that his mind and body were both coming back under his control. It took him a few moments, but he remembered what he was feeling.

Guilt and regret.

This was his fault. And he hated himself for it.

Slowly smiling, she reached up, placing her hands on his shoulders. She pushed herself up, angling herself a certain way. "Shinichi is going to try to kill you. Can you see him? On the rooftops behind me?" she whispered in his ear.

Hideo didn't want to take his eyes off her, but he looked. He could see a small figure in the distance. There was no doubt that it was Izumi, preparing to kill him.

"You should let him kill me," he spat, his hatred for his own existence bubbling over.

* * *

Shinichi flinched, lowering his right hand, the rock feeling much heavier than it had only moments before.

"What's wrong, Shinichi?" Migi demanded. "Why didn't you throw?"

He hesitated. "Kayoko is up there. She's blocking me." He paused, squinting, focusing in on the girl and the parasite she was protecting. "She's bleeding bad. He hurt her, but she… she's protecting him."

Migi simply replied, "That's love, isn't it?"

* * *

"I won't let him kill you." Kayoko glared at him fiercely, her words strong as she held herself close to him. "If we're dying, we're dying together."

He hesitated. "It's not right… if you die," he breathed, repeating the mantra that he'd said over and over in the months that he'd known her, even though he'd had the chance to take her life so many times. It was the only reason she was alive in his eyes, although if he thought about it, it wasn't much of a reason at all.

A soft smile came over her. "Yuko did something to you in the Fine Arts room, didn't she?" He nodded.

"I can't morph back into human form." Showing her, he tried, but his face only ended up as a skin-colored blob of flesh, some of it half burned from the acidic liquid he'd been drenched in. "There are too many dead cells. They interfere with the communication to the rest of my body."

She ran her fingers down his body, feeling the bullet holes in his skin. She flinched, but did not pull away. "And those officers shot you."

He nodded again. "I don't blame them. I am a murderer." He paused. "A monster," he added quietly.

"It wasn't your fault." She smiled again, the smile he'd come to know over the course of his lifetime as a fully functional almost human. "After all, you can't control fate, right?"

"I tried."

She moved her hands back to his shoulders. Hesitating, she reached for his true face. He flinched away, thinking that she would be disgusted if she touched him. But she kept him steady. She gently touched his true face, feeling his true self for the first time.

"Does this hurt?" she murmured.

He shook his head. "No. I can barely feel anything. My cells are still dead," he confessed.

She bit her lip and grabbed at her grey skirt, ripping a large strip of fabric off of the bottom of it. "I'm going to try to rub some of the dead cells off, okay? So you can try to shift back to human form? Will that work?" He said nothing, simply lowered his head to be within her reach.

Her touch was gentle. He felt himself leaning into it, fighting to keep his eyes open. He kept one of his eyes locked on Izumi, preparing to pull Kayoko out of the way, should he attack. Another turned its gaze upon the piercing wound that his blade had caused in her side. He fought to keep from flinching at the gory sight. Hatred for his own being filled him.

"I hurt you."

She hummed. "I told you that it's okay. We'll treat it as soon as we can get you back to safety." She smiled at him, continuing to rub away with the fabric.

He could feel some sense of control coming back to him. He gently reached up, taking her hand in his, gently pulling the fabric out of her grasp. "That's enough. I'll be okay from here. I want to keep you from bleeding out." He pushed the grey strip against her side, like he'd done that first night when she'd been lying on the kitchen floor, bleeding.

"What about you? You're full of bullet holes," she protested.

He concentrated, pulling his blades back to him. He could feel his human form coming into shape again, the eyes and the hair all back where they belonged. He was Hideo Shimada again, and he was back in control of his own being.

"You're only a human," he finally replied, gazing down at her with his human face. "You're fragile, and I can't let you die."

She smiled, knowing what he was about to say. "Because it's not right?" she guessed, knowing what his reasoning was. He nodded again. She paused, her smile falling from her face. "Hide… we can't stay here anymore. Not after that loss of control that you had."

Looking down, he felt something stir in his gut. He could place it faster than he had before. It was remorse, where he felt such intense regret and guilt that his heart – his slowly-beating, barely-alive heart – throbbed painfully in his chest.

"I didn't mean for this to happen."

Her hand reached up to cup his face reassuringly. "I know you didn't." She smiled as his hands came to rest on her shoulders, him staring down at her, his usually blank eyes starting to show a twinkle. "But we have to have a next move. What do you want to do now?" she asked softly, letting her hands fall to rest on his chest.

"I want to live," he replied immediately. "I want to live with you."

* * *

Migi perked up. "I can feel something…" Shinichi glanced at his hand, which had moved to stare at the building. "It's strong. Much stronger than any other signal I've ever felt before," he explained, eye narrowing.

Shinichi frowned. "What's he feeling?"

"Many things at once. His thoughts are no longer disjointed, but his signal has increased. He is more powerful than he has ever been."

"Migi, what is he feeling?" the human half demanded.

Closing his eye, the parasite thought. There were many different signals that he had to sift through. "Most of them are emotions I am unfamiliar with. Love is one of them, but the others… I suppose that I can sum them up as an uncontainable desire to live," he finished, opening his eye once more.

Hesitating, Shinichi looked to the school rooftop. He saw how they were wrapped in an embrace, Kayoko's back still turned to him, angled so he could not kill Shimada. From where he stood, they looked like any other human couple.

"Can you hear his thoughts?" he finally asked.

Migi glanced at Shinichi in confusion, but nodded. "Yes. He is thinking the same thing, over and over."

"What is it?"

"He is thinking 'I want to live with Kayoko.'"

* * *

She beamed. "Then, let's run away from here. Far away, where they'll never find us!" she exclaimed.

Kayoko's smile was bright, brighter than he'd ever seen it.

Maybe it was because it was a ray of light after the darkness that had just happened. Or maybe it was all of the emotions that were flooding into his body at once. Or maybe it was the way that he felt so human, more than ever.

Or maybe it was because he realized that his way of living was not living. It was just surviving.

It had none of the happiness or laughter that existed within human lives. It was empty and cold and lonely, and Hideo was tired of living that way. He wanted to do more than just survive. He wanted to live.

 _I want to live with Kayoko._

Perhaps it was a bit much to presume that it was the emotion that humans called "love." He had yet to experience anything like it, and that emotion was a powerful thing. It was the driving force behind many human stories. Many people used love as a way to motivate them, drive the decisions that shaped their entire lives.

A monster like him could never feel love. He didn't deserve it.

"Hide? Did you hear me?"

He heard her.

Slowly, he pushed the corners of his lips up in a gentle smile, softening his gaze as he stared at her. She didn't show the shock if she felt any. She just returned his smile, her beaming smile growing smaller, until hers mirrored his.

"Yes. Let's run away."

Even if he wasn't human, even if he would never fully be human, he would get close if he was with Kayoko. He could become something similar to Izumi. He could become an inhuman being that was caught between the lines of human and not.

"Let's go somewhere far."

And even if he wasn't human, even if he thought he didn't deserve to feel love, he figured that, maybe, just maybe, he deserved to feel happiness.

After all, every human deserved happiness. Why didn't he?

"As long as I am with you, I think that things will be fine."

His tone of voice didn't change. He still had the emotionless way of speaking, but that didn't bother him. It wasn't his tone that mattered to him. It was the message that he said, the words that he carefully selected in order to let Kayoko know how important to him she was.

She clearly understood, as she reached forwards, hugging him. She locked her arms around his neck, holding him close. "I'm okay if it's with you. You saved my life more than once, Hide. I want to help you, now."

"You do," he replied softly, returning the hug as best he could. He was sure that it was awkward, but it was all he could do. "You make me feel more human. I understand how you said 'love makes people do crazy things.'" She flushed, but he continued. "I can feel the way you can now. And it's because you taught me how to do so."

Kayoko was crying, but she was still smiling. "These are happy tears," she assured him. "I'm just… so glad that you're alive."

* * *

In the end, Shinichi never threw the rock.

He couldn't bring himself to murder someone who was still human. Especially not someone who he'd nearly killed with his carelessness and anger. Not someone he cared about.

Even if it meant taking out one of the inhuman creatures that he hated so much, he didn't want to lose what made him human. He wasn't yet ready to give up his humanity just so he could fulfil the angry hole in his heart. He wasn't even sure if killing Shimada would fill that hole.

Somewhere inside him, he was glad he didn't kill both of them.

He was glad that they had disappeared before the police reinforcements arrived at the rooftop. He had turned away for a moment, and they were gone. He was glad that he had even given them that chance. He was glad that the police, when they had stormed Kayoko's house, where she had once lived with her parents, they only found the house void of all personal belongings.

After all, she was never legally living at Hiroshi's house.

"Shinichi, where are we going?" Migi asked as they walked down the empty streets. "I thought you wanted to never see Shimada again."

He smiled dryly. "It's not Shimada I want to see. It's Kayoko."

"You'll see both of them. They are practically inseparable now." He ignored Migi, choosing to believe that this was the final time he'd get to see Kayoko, his old friend who he'd nearly killed.

He wanted to ask for forgiveness, even though he was sure that she'd tell him that there was no need to. To him, there was. He had pushed her away, called her a traitor. He tried to make it up to her by not giving away her location, the place she truly lived with Shimada.

The apartment building was hidden away in the corner of the street. He found the address, the one Kayoko had given him during the funeral, and knocked on the door.

A pair of unfamiliar eyes met his as someone opened the door.

Shinichi's eyes went wide, seeing the familiar face with all new features. "Shimada…?" he practically breathed, shock seeping into every part of his body.

"Hello, Izumi. Migi."

The parasite had changed completely within the week. He no longer had neatly-kept, brown hair. Instead, his hair was a messy black. His eyes were no longer those blank, emotionless eyes that every parasite had. Instead, they sparkled with something akin to life.

"I don't understand," Migi murmured. "How could this be? Your signal is strong now that I know it's you, but… I didn't recognize that it was you at all."

Shimada managed the smallest of smiles. He didn't seem threatening at all. In fact, he seemed like less of a threat than Migi, and Shinichi actually trusted Migi. "It's because I let myself feel. Emotions make us human, and being human makes us less of… whatever it is that we are," he replied easily. He opened the door wider, gesturing for them to come in. "I knew you were coming. Kayoko's getting some snacks ready with the food we have left."

Shinichi slowly entered the apartment. It was barren. There was nothing decorating the walls or the hallway. There was nothing to show who lived in the apartment, or even that it'd been inhabited at all. No photos or paintings, nothing of the sort. There was barely anything, save for a few suitcases that sat by the door. They were all closed, stacked one on top of the other.

"Are you… going somewhere?"

Nodding, the parasite closed the door behind Shinichi. "Yes. We're leaving. We're going to try to get a fresh start in a new city. Maybe a new country if that's what we have to do." He paused, looking to his former rival. "I know that we can't live here anymore. I feel bad for taking her away from her friends, but… well, it was her idea." He chuckled.

"Her idea to do what?"

"Run away, of course." Shimada softened as the conversation shifted to Kayoko. "We're both ready. There is barely anything left for either of us here."

Shinichi shook his head, slowly trying to digest everything that Shimada had just dropped onto him. "Why… what made you decide to go?" he asked almost disbelievingly.

The now black-haired boy hesitated, bowing his head. "After… after I came to my senses, I felt regret. I hated myself for what I'd done. The day before it happened, I swore I'd never harm another human being. But I wanted to protect the secret that Kayoko and I held. If it came down to it, I would have let you kill me," explained Shimada.

The two walked into the living area together, one that was connected to both the dining area and the kitchen, which were the same.

"What changed your mind?" Shinichi was genuinely curious now.

Glancing towards the dining area, Shimada nodded towards the girl whose hair was in a neat bun atop her head as she wrapped a boxed lunch in a blue cloth. "She did. She was ready to die alongside me. When I saw that, the only thing I could think was… I want to live." He glanced to the human, a small smile on his face. "Haven't you ever felt that way?" he asked quietly, his tone sounding like it was begging Shinichi to verify his feelings.

Shinichi slowly nodded. "Yes. I have," he murmured.

"Then you know exactly what I mean. I've come to understand something within the past few days, Izumi." He looked directly at Shinichi, his eyes sparkling with the life that a parasite should never have been able to show. "Living is something that humans do. Surviving is what every other species does. I want to live. I want to be alive."

Slowly realizing what the other boy meant, Shinichi nodded. He understood. He knew why Shimada and Kayoko were leaving.

"Run as far away as you can, Shimada. And don't look back for anything."

Shimada slowly smiled once more. "I can't promise that. If Kayoko lags behind, then I'm going to look back and wait for her. She _is_ the one keeping me alive, after all."


	8. us

Parasyte -the maxim-  
Symbiosis  
Chapter 8: Us

It'd been a year since they'd left their old town, since they'd fled from the world.

And it'd had been a year since all the fear of the parasites settled down.

After the government figured out how to identify a parasite, thanks to a strange incident in which a body of one of them was found, most of the remaining parasites went into hiding. Very rarely did they ever come out, and if they did, it was because they couldn't fight their killer instincts forever. The ones who learned to adapt were the ones who survived the eradication of their species. They learned to act the part as humans, just to ensure that they could survive.

But none ever truly learned what it meant to _be_ human.

"The mystery of the mincemeat murders remains unsolved… but a panel of judges are going to try to unravel the mystery?" Hideo scoffed at the ad on the television, glaring at it like it'd offended him. "Some stupid show about a stupid subject. They're just trying to make headlines."

Rolling her eyes, Kayoko dropped onto the couch next to him. "Yeah, well, that's what the news does. It's their job to make headlines," she replied.

He changed the channel back to their television show that they'd been following for the past few weeks. It was a rerun, but it was much better than the stupid news shows that were celebrating the anniversary of something so morbid and so uncomfortably familiar for Hideo.

"Doesn't mean that they have to drag up those memories. The events happened a year ago."

"That's long enough for the vultures to swarm." She glanced at Hideo, who was still glaring at the television with crossed arms. "Are you still beating yourself up over the school?"

He sighed, hanging his head as he slumped, his arms falling to rest at his sides. "How can I not? Every time I remember what happened last year, I remember that in one day, I more than tripled my body count." He rubbed his temples, trying to force the memories away. "I'm not proud of what I did," he mumbled.

Covering his hand with both of hers, she moved to look him right in the eye. "You're acknowledging your mistakes. That's all anyone can ask of you."

"The families… they must want me dead."

She frowned. "But what would that solve? Nothing. That'd just start more senseless violence, because all that stuff about revenge? It's all lies. Revenge helps no one. It doesn't bring back the dead. It wouldn't even make them rest easier. It would just turn more people into murderers, and the last thing this world needs is more murderers," she replied, turning his hand to face upwards, tracing characters into his palm.

They were all characters he was familiar with. They spelled out words that he clung to in order to remember that he was not just a mindless killer. He was someone with a life of his own now. He had reasons to live.

 _Hope. Happiness. Life. Love._

 _Us._

The last word was a new word, one she'd never traced against his skin before.

He glanced at her, seeing her staring down at his palm. She slowly traced the characters again, as if to repeat the word to him.

 _Us._

"Us?" he murmured.

Nodding, Kayoko tucked her hair behind her ear. "Yeah. Because remember what we agreed? There isn't much of a difference between our species." He still looked confused, so she continued, "The differences aren't what put our kinds at odds. It was how similar the two species are. We all have the same composition, the same thoughts, and the same goals. The only differences are in how we achieve those goals."

"I don't understand."

"What I'm saying is that everyone went about it the wrong way." She gently placed her hand in his, curling her fingers around him. "Both species separated themselves from the other. They fought instead of working together. They all had a mentality of 'us' versus 'them.'"

Realization dawned upon Hideo as he began to understand what she was saying. "You're saying that there is no 'them,'" he finally said.

She nodded, looking up to him, her eyes sparkling with maturity and wisdom beyond what a human her age should have had. "There's only 'us.'"

* * *

Shinichi was trying to live without Migi.

It was hard, especially after all that they'd gone through with each other. After coming to understand each other, Migi had just decided to disappear one day. Even after a year of his right hand being dormant, he still found himself longing for the company of someone who he could say truly understood him, in ways that no one else could.

Sometimes, he even caught himself talking to his right hand, like it would respond. It never did.

It was no longer "Migi." It was just his right hand.

Loneliness crept up on him sometimes. Only a year ago, he was fighting for his life against otherworldly creatures. He was struggling to accept that he was walking a thin line between human and not. He had a foot in both worlds, and they were both difficult for him to find a balance between.

Once he did, he found that he no longer had to perform that balancing act.

He could be human again.

Somehow, it was like he'd forgotten how to be "human," or, at least, "human" the way that he used to be. Human in the way he saw the world as filled with black and white. Human in the way that he perceived threats and danger. Human in the way that he wanted to fight fate whenever it did something that he didn't quite agree with.

But his entire view of the world had changed, thanks to the time that he'd been stuck between the worlds of parasites and humans.

He understood now that the world was painted in shades of gray, not just black and white. There weren't just two sides, but many different perspectives of the same world. He understood that there were some threats he could face and some he had to run from. He understood that fate did what it wanted without any regard for how he felt.

He understood that there were things that he could not change.

"Shinichi!"

Some of them, he didn't want to change.

He looked up, seeing Satomi wave at him. He waved back with a smile, then stood.

"Did I keep you waiting long?" she asked cheerfully.

He shook his head, feeling something like peace wash over him. "Not at all," he replied, studying her smile, wanting to memorize it, so he never forgot it.

It had taken Satomi a while to truly come to terms with what had happened involving Shimada and Kayoko, and later Shinichi's involvement with the parasites. She'd been thrown into the center of the conflict, as she had later befriended Kana, who had also been killed. She'd been forced to watch as Shinichi – the Shinichi she knew and cherished so dearly – vanished, only to return after one of the creatures showed some form of humanity right before she died.

Ryoko Tamiya had shown Shinichi that both of their species were similar in some ways – more than Shinichi originally expected, having labelled parasites as monsters and humans as nothing but human. Both species were fragile creatures, who had the ability to sacrifice themselves for those that they cared about. She'd shown that she could feel, hurt, and bleed in the same ways that he could.

They were more alike than they were different.

 _"_ _Thank you."_

She'd thanked him right before she died, wilting as her body hit the ground.

She'd left him with her baby and her parting smile. Two things of hers that were more human than he ever thought that parasites could be.

Even after all of the things that happened, Shinichi never told Satomi what he was, what he had been. He never told her that he'd had one of those things in his right arm, which was why he changed, why he became so bitter and angry and vengeful. Why he was filled with so much hatred. He never told her, and she had never pushed him to tell her.

He'd told her about his mother, but she'd just held him, and told him that he didn't have to talk about it, if he didn't want to.

He didn't talk about it.

He'd only melted into her arms, holding her the same way that she was holding him. He'd thought back to the way that Shimada held Kayoko when they stood on the rooftop, protecting each other from the dangers that surrounded them.

It was the same way that Satomi held him.

A hug filled with delicate, fragile care. It was soothing and warm, overflowing with all of the love and affection that could be forced into the hug.

It was so _human_.

 _"_ _Living is something that humans do. Surviving is what every other species does. I want to live. I want to be alive."_

Thinking back on Shimada's words, some of the last words he'd ever heard the parasite speak, Shinichi understood. In that moment he had sympathized with the parasite, who had decided that he was going to live in a different way. He was going to be as human as he could, in the ways he knew how. He was going to walk the line between parasite and human, the way Shinichi had.

Somehow, Shinichi knew that Shimada had been successful in finding a new life and living it as a human. After all, he was lucky to have Kayoko to lead him in the right direction. He knew that she would pull Shimada back if he ever strayed from the path that led to humanity.

Just like Shinichi had Satomi.

"Shinichi?" He snapped back to his reality, seeing Satomi gazing at him, half worried, half teasing. "Where did you go this time?" she asked.

Smiling sheepishly, he stuck his hands in his pockets. He turned his gaze towards the unchanging blue skies, the ones that had been the same shade, even a year ago. "I was thinking about Kayoko and Shimada," he admitted. "I figured that they must be happy, wherever they ended up." He looked back to Satomi, who was watching him.

She smiled as well, her entire face softening. She reached out to take his right hand. She'd avoided holding it only a year ago, but now, she was unafraid. There was nothing left for her to be scared of.

He was Shinichi Izumi again.

"They probably are," she said softly. "I wonder where they went, though. I can't help but think about her sometimes, and wonder if she's still out there."

Satomi knew that Kayoko hadn't died that day, like many had assumed.

When the police had gotten to the roof, they had only found blood splatters from both parties. The blood from Shimada's bullet wounds and the blood from Kayoko's gash. But they didn't find either of the teenagers.

They never found Kayoko's body, but after three months of searching for both her and Shimada, they'd written her off as dead. She had no next of kin, but the school mourned her, just like they had the rest of the students who had died in the massacre.

Shinichi was the only one who'd seen Kayoko after she vanished off the rooftop. When he'd gone to see her on the day they'd left, she'd welcomed him with open arms, even after all he'd done. She'd greeted him with that same smile that she always did.

 _"_ _I know why you're here. Don't apologize, Shinichi. Just promise me that you'll live well. Make Satomi happy, and make yourself happy. Okay?"_

She'd made him swear that he'd put his own happiness first.

At the time, he wasn't sure what she'd meant by "live well." He didn't see how he could have, not with all the death and destruction that was surrounding him.

But now, he knew.

She wasn't just telling him to "live well." She was telling him "be happy" and "forgive yourself." She was always good at reading him like that. She knew exactly what he needed to hear, even before he needed to hear it. She'd offered him a smile, before explaining that he'd caught them right before they were leaving. They'd chatted for an hour, but then, Shinichi was alone in the apartment.

The suitcases had disappeared after he'd gone to the bathroom. And with them, Kayoko and Shimada had vanished, leaving no trace that they'd ever been there, except for a photograph sitting on the dining table.

He had to smile, remembering the photo she'd left behind.

It was one that Shinichi and Kayoko had taken as children. They were on the playground, with Shinichi holding Kayoko on his back. He was beaming up at her, proud of how he'd managed to lift her up, even though his knees shook, while Kayoko was smiling right back, congratulating him on a job well done.

There was a note on the back, hastily scribbled in marker. _You are a good man_ , she'd written. Those were the only words she left him with, but they meant a lot to him.

He was doing the right thing. He had _done_ the right thing. He'd let them go, let Shimada live. He didn't become a killer, and he'd given the two a chance to start anew.

"She's out there. I'm sure. She and Shimada are probably together right now." He squeezed Satomi's hand. "Just like us."

* * *

Hideo Shimada couldn't tell the future.

For all his intelligence, the one thing he would never know was what would happen next.

He didn't know if there was a "happily ever after" written in his future. He didn't know if he would live as long as he thought he would. He didn't know if he'd be able to keep living as a human being or if his true self would be exposed.

He didn't even know if it would rain the next day.

All he knew was that he was living, at that moment. He was alive in every sense of the word. He was living the way that a human would.

At that moment, he was human.

In that single frame, a single second, a snapshot of happiness in a painfully long life, he was human.

He was lying on the couch of his apartment, the one he'd helped pay for with a job he'd gotten the human way. The television was on, playing that movie that she loved so much. He finally understood why those humans did such strange things for each other. His arm was wrapped around the girl who was lying over him, her own arm draped over his stomach. Her head was on his chest, listening to the heart with a beat stronger than it had been a year ago.

Looking down at her, he wondered if she knew the answer to some of the harder questions. He wanted to know more, he wanted to _be_ more.

"Kayoko. What are we?" he finally asked, his voice carrying throughout the small room.

Silence answered him for a moment as she stared up at him, her eyes showing only confusion.

But that confusion quickly disappeared as she beamed.

She broke their gaze, moving to rest her head on his chest again. She breathed in and out, her breaths matching the rhythm of his heartbeat.

"We're 'us,' Hide."

 _Us._

That had a nice sound to it.

* * *

 ** _fin._**


End file.
